This invention relates to a cell culture vessel and a cultured cell cultured in said vessel.
In the recent years, the technique of cell culture used for the purpose of medical treatment has progressed, and is actually applied to transplantation of the skin, etc. The application of cell culture is not limited to small quantity of cells and tissues such as the skin, but the progress is being directed toward the auto-transplantation and hetero-transplantation of complicated organs such as cornea, teeth, bones, organs, etc.
For the culture of cells, vessels made of glass or resins, such as Petri dish and the like, are used. For example, a Petri dish such as mentioned below is disclosed. A collagen solution having a prescribed concentration is poured onto a culture vessel by means of a pipette so that the surface of the vessel becomes coated uniformly, and thereafter the coated dish is dried for a period of 15 minutes to 72 hours. Otherwise, a collagen solution having a prescribed concentration is coated onto a stretchable culture base material such as silicone film and polymerized in an incubator at 15-42° C. for 20-120 minutes, after which the stretchable culture base material such as silicone film is left standing under an UV lamp for 15 minutes to 72 hours. After the collagen has been dried, the collagen is again moistened with a phosphate buffer solution, and thereafter the collagen is stretched to an extent of 10-40% and fixed to give a dish for use in cell culture (see JP-A-2002-142751 (Example A)).
Further, as another type of cell culture vessel, the following is disclosed. Thus, the bottom of a culture vessel is coated with a polymer which shows a hydrophilic nature at a temperature and a hydrophobic nature at another temperature, and the polymer is immobilized by UV irradiation or the like, whereby a culture vessel suitable for peeling of cell after the culture can be obtained (cf. JP-A-5-244938 (Example 1)).
According to the first method mentioned above, a cell can be cultured on collagen which has an affinity to the cell. Contrarily, however, the adhesive force between cell and culture vessel is so strong that the cultured cell is difficult to peel off from the vessel. Regarding this adhesive force, there has been a problem that mechanical peeling of the cell brings about a physical injury of the cell, so that when the cell is subjected to a chemical treatment using an enzyme such as trypsin or the like, the membrane protein on the surface of cell is broken and percentage of fixing of cell into tissue, after transplantation, decreases.
According to the second method mentioned above, the problem of peeling can be solved by adjusting the water-philic nature of the surface of culture vessel and thereby decreasing the adhesiveness of cell surface. If such a measure is taken, however, the state of cell culture vessel surface is limited to that of specified material. In addition, the problem how to prepare an arbitrary surface state well coping with various cells, how to shorten the time period for producing a culture vessel, how to transport the nutrients to the central part of sheet-form cell, how to accelerate the discharging of waste-materials, etc. have been remained unsolved yet.
It is an object of this invention to provide a cell culture vessel which is simple and convenient in structure, capable of preventing the injury to cells at the time of peeling, and able to accelerate the transportation of nutrients and discharging of waste materials.